Here is the full list of all 12 Dark Room achievements.
Unlock the first door in the game
Solve the first puzzle in the game
Find the computer password
Find all letters in the game
Find the exit door password
Unlock the first ending of the game !
Unlock the second ending of the game !
Unlock the third ending of the game !
Start the purgatory mod
Start the green stone mod
Start the top secret mod
Listen to the end credits music